There exist many different ways to propel watercraft. One way is to use what is known as a jet propulsion system which is powered by an engine of the watercraft. The jet propulsion system typically consists of a jet pump which pressurizes water from the body of water and expels it through a venturi as a jet rearwardly of the watercraft to create thrust. Usually, a steering nozzle is pivotally mounted rearwardly of the venturi. The steering nozzle is operatively connected to a steering assembly of the watercraft which causes it to turn left or right to redirect the jet of water and thereby steer the watercraft.
As would be understood, the more the steering nozzle can be rotated relative to the venturi, the more maneuverable the watercraft can be. However, beyond a certain angle of rotation of the steering nozzle relative to the venturi, the change in direction of the water from the venturi to the steering nozzle becomes too abrupt, leading to losses in propulsive efficiency. This loss in efficiency is due the increased turbulence and friction created as the nozzle is increasingly rotated. This can eventually lead to choking of the water flow in the jet pump upstream of the venturi, which in turn leads to a reduction in engine speed (because of the impeller in the choked flow) and therefore thrust loss. For these reasons, the maximum angle of rotation of the steering nozzle relative to the venturi has been limited to angles of about 20 to 25 degrees.
Therefore, there is a need for a jet pump assembly which permits water exiting the venturi to be redirected by greater angles.